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In 1988, after reading two passing boaters didn’t “want to be bothered” with young men in an overturned rowboat (the one young man later died), Jara was angry. She wondered what she could do to remind people of the importance of kindness when she settled on Be Kind to Humankind Week, now through Aug. 31. There’s Be Kind to Animals Week, so why not designate one for humans?

“It’s hard to believe you can do a little bit and it changes the world, but I don’t know,” she told Medical Daily. “If you stop to think about it, if you do things in your own life and communities to be kind, it would really make for a different world.”

Jara initially spread word of her campaign by hand; she wrote letters to her favorite celebrities to see if they would promote kindness on their platform, receiving her fair share of signed and copied form letters. Eventually, as technology improved, her message started to spread. Then, in 1995, the non-profit Random Acts of Foundation was founded and kindness started to catch everyone’s attention, including Oprah (who personalized her response to Jara way back when).

It’s not just Oprah. Recent studies published in The Journal of Happiness,Nature Neuroscience,and the Journal of Social Psychology has found kindness can lead to greater health and happiness. Good deeds make people feel good, even when performed for as little as 10 days. They help cultivate new connections in the part of the brain associated with happiness and enhance well-being. One study from Emory University even found being kind releases endorphins, the same chemicals that are linked to runner’s high. So a helper’s high, if you will.

Given Jara’s week of kindness and some pretty convincing science, we decided to put it to the test. And what could be kinder than buying a few unsuspecting New Yorkers their afternoon green juice?

We set out on a humid Monday afternoon to buy (if only slightly ambush) New Yorkers lined up at food carts for an afternoon snack, from green juice to ice cream. It wasn’t without hesitation, but each person allowed us to pay for their snack and remind them something as small as this can have a big effect. Perhaps surprisingly each person suggested they would return the favor by paying it forward. Everyone knew how great it was to be kind — they just needed a little reminder. (We still feel bad about that snow cone, though.)

The point is, we see what Jara is saying. We may have only made a small, local effort to be kinder to the people we’ve likely been smashed up against on the subway, but the payoff has potential to be huge. If everyone pays forward a random act of kindness, imagine how long before everyone shows kindness when they can do it without being reminded it’s just the healthy and happy thing to do?

“I’m just like anybody else,” Jara said. “I can be grumpy and in my own little world. But rather than be in my own world, I’m going to try to promote kindness each day. It’s not fancy stuff, but it’s a good thing. We can’t always be up, but we can help each other get through each day in a positive manner. What goes around will come back without even having to look for it.”

Now it’s your turn. All week long we’re celebrating kindness on our social channels, and we want to know how you show kindness toward both yourself and others. Share your stories, photos, videos, quotes, and what have you using the hashtag #MDbekind — and we’ll share some of our favorites.